Thanks to
@Morgan for reminding me of Little Legs Fabrics at Scorton. I visited yesterday afternoon as it's not to far away from home.
It's speciality is jersey fabric, various weights, plain and printed, not just child-friendly designs, AND you can get your pdf patterns printed at A0 size for £2 per sheet. I'm not sure of their postage prices/service but the ladies were friendly and helpful and there's a choice of 3 tearooms, 2 garden centres to visit within a mile or so. I did leave with a length, or 4 of jersey but plenty left for another week.
https://www.littlelegsfabrics.co.uk/